Overview of speech sound confusions in adults and children with cochlear implants
The goal of the project is to create a comprehensive overview of the typical speech sound misperceptions in Norwegian for prelingually and postlingually deaf children and postlingually deaf adults with a cochlear implant (CI). The speech sound identification ability of CI-users with the hearing impairment auditory neuropathy will be investigated particularly.
Such an overview will be useful both for the clinicians who adjust the sound in the CIs, and for the speech therapists and the teachers of the deaf who work with training of hearing. It will also be useful for the researchers who work to improve the existing and develop new CI systems. In conjunction with the discussion in progress in Norway, about whether or not adults with CI should be entitled to one or two implants, this is also a relevant issue, because the study aims to show whether CI users will discriminate speech sounds better with two than with one CI.
Theory and method
The project is a quantitative, cross sectional study. The theoretical basis of the project is central theories about speech perception, and the project is also based on similar experimental studies in other languages such as Dutch, English, Finnish and German. By means of a nonword test, it will be investigated how well the participants can identify Norwegian speech sounds, and the test is designed so that the degree to which the test measures the hearing ability of the participants, is maximized.
In the data collection, recorded one- and two-syllable nonwords will be played to the participants, who will be asked to repeat what they hear. Their responses will be recorded and the sound recordings will be transcribed with phonetic notation (IPA) by two independent trained transcribers. The analysis will be done by statistical methods, and some acoustic analysis of the recordings will also be performed.